In the lead-up to the EU referendum immigration featured as a key issue, but despite calls to “take back control” of the UK borders there is only speculation about how immigration will operate once the UK withdraws from the EU.

Recent figures suggest there are 2.1 million EU nationals working in the UK at present, so on a practical level it is difficult to foresee a situation where these individuals will be required en masse to leave the UK, and for many employers this would be a nightmare scenario.

In the days following the Brexit vote I received several enquiries from EU nationals with long-term residency rights keen to avoid uncertainty by becoming British nationals, but for others it is important the preferred option is outlined at an early stage.

While the UK negotiates with the EU, either before or after formally triggering the Article 50 procedure to leave, the law will remain as it currently stands. EU nationals and their family members will be able to continue to come to the UK for work, self-employment, to study or to live as a self sufficient person. However, the position once the UK leaves the EU will depend on the exit arrangements negotiated between the UK and the EU.

During the campaign to leave the EU it was suggested any changes would not impact on people already living in the UK so it is possible the UK Immigration Rules might be amended to grant visas to such individuals.

However, it is not clear whether or not this protection would extend only to EU citizens in the UK on the date of the referendum, to EU nationals living in the UK on the date the Article 50 exit procedure is triggered or to all EU nationals in the UK when it leaves the EU.

This results in a great deal of uncertainty for individuals and businesses who are unsure about whether key staff will be able to remain in the UK or the potential timescale for their departure.

One option that has been suggested is for the UK to become a member of the European Economic Area (EEA), a position already adopted by Iceland, Liechtenstein, Norway and Switzerland, to retain access to the single market but this is likely to come at a cost.

Each of these countries has agreed, as a pre-condition of their membership of the single market, to respect free movement of EU nationals and it would seem likely the UK would be required to make a similar commitment.

If this were to be the case the practical impact on immigration would be minimal as EU nationals would continue to be able to move to the UK on the same basis as they currently do.

This might be the best option for EU nationals and for businesses reliant on EU workers but is unlikely to be seen as acceptable by many of those who voted for the UK to leave the EU.

Boris Johnson has suggested the UK could retain access to the single market but without joining the EEA. Instead, he has suggested the UK could introduce a points-based immigration system. The UK already has a points-based system for individuals from outside the EU, although in recent years many of the categories have been closed or reformatted so they no longer resemble the Australian model where an applicant’s qualifications and age are assessed on a sliding scale. This could be possible within the current immigration framework but substantial amendments would be required.

The UK also has a sponsored worker scheme, known as Tier 2 visas, and this could be used by employers to fill skill gaps. However, there is a cap of 20,700 new visas per year and this is already stretched by immigration from outside the EU, so it would be necessary to make the unpopular decision of relaxing immigration laws if this system was to be relied upon.

It is difficult to foresee the changes to immigration law that might follow the Brexit vote, and unfortunately this is only likely to lead to uncertainty for businesses and individuals.

Long-term residents can safeguard their position by applying for British passports but, for those that are not eligible, it is important a coherent immigration position is set out sooner rather than later.

This article first appeared in today’s Herald.